I think it's a little more simpler than that.
Typically you have your GUI window which is similar to
::Example_Window <- GUIWindow( VectorScreen( ScreenWidth - ( ScreenWidth / 1.5 ), ScreenHeight - ( ScreenHeight / 1.5 ) );
Which is correct.
The next call would be to place an code either in a command or withing a button or hotkey/bindkey.
The code for that would be
for showing the window
::Example_Window.Visible = true;
For disabling that window
::Example_Window.Visible = false;
If you have any more help please feel free to ask more,.